Michigan reports first 2 US deaths from cyclospora outbreak

Two people have died in Michigan from cyclospora infection, marking the first confirmed US deaths from the microscopic parasite, state health officials announced Monday. Both victims had underlying health conditions that may have been exacerbated by the severe dehydration caused by the intestinal illness, according to the Michigan Department of Health and Human Services. The department declined to release additional details about the individuals.

The deaths are part of a larger outbreak that has spread across nine states, with health officials tracing the source to lettuce from Mexico served at Taco Bell restaurants. While cyclospora infections are rarely fatal, they can be particularly dangerous for vulnerable populations, including the elderly, young children, and those with weakened immune systems.

The parasite and its symptoms

Cyclospora cayetanensis is a single-celled, spherical parasite that infects the bowels and causes cyclosporiasis, an illness characterized by watery diarrhea that is often frequent and sometimes explosive, according to the Centres for Disease Control and Prevention (CDC). Other symptoms can include cramping, bloating, nausea, loss of appetite, and fatigue. The infection spreads through fecal contamination, typically when produce is irrigated with contaminated water. Outbreaks are most common in late spring and summer, as the parasite thrives in warm weather.

Although cyclosporiasis is rarely deadly in healthy individuals, the intense diarrhea can lead to severe dehydration and electrolyte imbalances, which can be dangerous for people with underlying medical conditions. In this outbreak, both Michigan victims had pre-existing health issues, highlighting the heightened risk for certain patients.

The Taco Bell outbreak

Health officials have linked the outbreak to lettuce from Mexico served at Taco Bell restaurants in nine states. The identification came after extensive epidemiological interviews and trace-back investigations. Consumers who visited Taco Bell during the exposure window may be at risk, and health departments are working to identify all cases.

This is not the first time cyclospora has been associated with fresh produce from Mexico. In previous years, cilantro, raspberries, and other imported items have been implicated in outbreaks. The parasite's resilience and the global nature of the food supply chain make it a recurring challenge for food safety regulators.

A decade of rising infections

While cyclospora remains less common than other foodborne pathogens such as salmonella and E. coli, the number of reported cases has increased significantly over the past decade. A particularly notable spike occurred in 2018 and 2019, when the CDC recorded thousands of infections across the United States. Many cases are never linked to a specific food source, and reporting gaps mean the true burden may be even higher.

Improved diagnostic tools and greater awareness among healthcare providers have likely contributed to the rise in detection, but experts also point to changes in global food production and distribution as factors. Imported produce, especially leafy greens, has become a frequent vehicle for cyclospora and other pathogens.

Response and prevention

In response to the outbreak, Taco Bell has removed the implicated lettuce from its supply chain, and federal and state agencies are continuing their investigation. Consumers are advised to wash produce thoroughly, though washing may not fully eliminate cyclospora, and to practice good hand hygiene. Anyone experiencing prolonged diarrhea, especially after travel or dining at affected restaurants, should seek medical attention. Health care providers are urged to consider cyclosporiasis in patients with compatible symptoms and to report cases to public health authorities.

The deaths in Michigan serve as a somber reminder that foodborne illnesses can have serious consequences. While progress has been made in understanding and tracking cyclospora, more work is needed to prevent contamination at the source and to protect those most at risk. As the investigation unfolds, public health officials will be looking for lessons to strengthen food safety measures and response protocols for future outbreaks.